A label-free, organic transistor-based biosensor by introducing electric bias during DNA immobilization

P and N type copper phthalocyanines as effective semiconductors in organic thin-film transistor based DNA biosensors at elevated temperatures

“…These devices detect target DNA strands by capturing double stranded DNA (dsDNA) onto the active layer of the OTFT. Physical adsorption of DNA, 16 electro-immobilization, 17 and chemical immobilization 18 have all been investigated for xing dsDNA, or single stranded DNA (ssDNA) probes, to the surface of an electrode or the semiconductor material itself. ssDNA has a linear structure comprised of four different bases which will bind with a complementary ssDNA strand to form a double helix (dsDNA) that orders the p orbitals of the bases.…”

A label-free biosensor based on organic transistors by using the interaction of mercapto DNA and gold electrodes

“…5 shows the difference in the sensor output and the transfer characteristics from the original device compared to the device with immobilized ssDNA or dsDNA. In OTFT-based biosensors, the saturation on-current ratio (I ratio ¼I on /I original , I original is the saturation on-state current of original device with V GS ¼ À40 V) is usually used to evaluate detecting sensitivity [19,20]. After immobilizing ssDNA2, the I ratio of the device is 0.38 which is less than that for ssDNA1 (0.67).…”

Different Work Regimes of an Organic Thin Film Transistor OTFT and Possible Applications in Bioelectronics

“…Another possible application could be a sensitive transducer in those sensors that request a current variation without interfaces interferences, [30].…”